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69-875: The Klasies River Caves are a series of caves located east of the Klasies River Mouth on the Tsitsikamma coast in the Humansdorp district of Eastern Cape Province , South Africa. The Klasies River Main (KRM) site consists of 3 main caves and 2 shelters located within a cliff on the southern coast of the Eastern Cape. The site provides evidence for developments in stone tool technology, evolution of modern human anatomy and behavior, and changes in paleoecology and climate in Southern Africa based on evidence from plant remains. Klasies River Cave

138-515: A bias towards sites where there is good preservation, skewing results and potentially obscuring the origin of behavioral modernity. Other studies that assert behavioral modernity rely on variables like climate, resource availability, and labor, which also influence behavior. Arguments that state brain size, social demographics and other factors are the cause of behavioral modernity are undermined by these outside variables. Complex behaviors include language and symbolic objects, which are not easily found in

207-476: A descriptive naming pattern for the observed soils instead of Singer and Wymer's classification system, however both systems are still used today. Sarah Wurz began directing excavations at the site in 2013 and continues today with a continued focus on microstratigraphy; her work is mainly within the Cave 1 Witness Baulk, a section that hadn't been excavated previously. The current work is focused on gathering data from

276-834: A higher quality diet which could lead to an evolutionary change in Homo sapiens. Samples taken from hearths within MSA I and Howiesons Poort levels identified parenchyma , heated bones and shellfish found together indicating the cooking of multiple food sources. The parenchyma samples came from underground storage organs, but preservation did not allow for determination of plant species. The abundance of plant species available year-round, as discussed in previous sections, would have provided many reliable energy sources for humans; cooking these starchy plants increases energy absorption. Site occupation patterns based on faunal, food source remains, and lithic evidence suggest that hominins were more mobile during

345-475: A more closed environment while later periods increase in grazing fauna associated with more open environments. This period is associated with MIS 4, a glacial period with cooler temperatures and lower sea levels. Shellfish that appear in tide pools are more common in HP which suggests a further coastline. Data from Pinnacle Point show that the climate during HP was variable and unstable with periods of drought. MSA III

414-495: A mosaic environment that included closed, drier areas with micromammals including moles, and open grasslands that favored grazing ungulates. This period is associated with an interglacial period (MIS 5e) and higher sea levels and warmer temperatures, which is supported by shell middens. MSA II shows a shift from MSA I. This period is associated with MIS 5d-a, with the early part of this phase associated with warmer temperatures shifting towards cooler temperatures later. During this time

483-566: A number of isotopic profiles was designed to eliminate 'noise' errors, that could have been contained within a single isotopic record. Another large research project funded by the US government in the 1970s and 1980s was Climate: Long range Investigation, Mapping, and Prediction (CLIMAP), which to a large degree succeeded in its aim of producing a map of the global climate at the Last Glacial Maximum , some 18,000 years ago, with some of

552-675: A paper of 1947 that the ratio between oxygen-18 and oxygen-16 isotopes in calcite , the main chemical component of the shells and other hard parts of a wide range of marine organisms, should vary depending on the prevailing water temperature in which the calcite was formed. Over 100 stages have been identified, currently going back some 6 million years, and the scale may in future reach back up to 15 mya. Some stages, in particular MIS 5, are divided into sub-stages, such as "MIS 5a", with 5 a, c, and e being warm and b and d cold. A numeric system for referring to "horizons" (events rather than periods) may also be used, with for example MIS 5.5 representing

621-551: A phylogenetic tree. Ancestral and derived traits vary with genetic drift , mutations , and other genetic factors that can steer evolution in many directions. Modern humans ( Homo sapiens ) originated in Africa and trace a lineage back to non-human primate ancestors there. For further discussion on human evolution, see human evolution , evolutionary genetics , and timeline of human evolution . Anatomically modern humans share traits with today's modern Homo sapiens. Remains from

690-565: A study found that the use wear did not relate to the same type of musical instrument used at the other MSA sites. Instead, the authors found starchy reside within the teeth of the rasp and suggest that the tool was used for plant processing rather than as an instrument or skin abrader, however this is not proven. A ground bone point dating to 80-65 ka and a charred bone with engraved lines come from Howiesons Poort contexts. Use-wear analysis found longitudinal striations consistent with longitudinal action (including arrow use); microstriations suggest that

759-520: A timeline of glaciation for the Plio-Pleistocene to be identified. It is now believed that changes in the size of the major ice sheets such as the historical Laurentide Ice Sheet of North America are the main factor governing variations in the oxygen isotope ratios. The MIS data also matches the astronomical data of Milankovitch cycles of orbital forcing or the effects of variations in insolation caused by cyclical slight changes in

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828-588: A total of 281 available edible plant species; these resources were less abundant within the smaller radius and would give reason for an extended foraging journey to acquire varied and less perishable nutrients. A majority of the food plants within these radii can be eaten raw. The association of animal and plant remains with hearths provides evidence that hominins at the site used fire to cook. Bones with cut marks and percussion marks from hammer stones indicate that meat and bone marrow were consumed. Cooked foods provide quickly digestible energy and would have contributed to

897-686: Is located on the border of the Tsitsikamma mountain range on the southeastern coast of Africa. The site sits within the Greater Cape Floristic region, characterized by the fynbos biome; however the Klasies River Cave environment is mixed woods and shrubby brushland and maintains a temperate climate . Klasies River main site is located on a sandstone cliff less than 1 kilometer from the Klasies River mouth and on

966-476: Is marked by a declining temperatures and receding coastline that would have exposed the Palaeo-Agulhas Plain . The faunal remains are variable and consist of wetland species, open environment grassland grazers, and Cape dune mole rats that prefer sand dunes. This period corresponds to MIS 3, a cooler environment with short warm periods. There is little data available to describe the paleoecology of

1035-502: Is not indicative of higher cognitive function or intelligence. Instead brain size may increase with social learning and increased perceptual and motor abilities. These increased abilities create a positive feedback loop that increases brain size via social learning and its impact on primate and hominin ability to acquire more nutrient rich food sources that favor brain growth. There is a clear relationship between brain size, sociality, and lifespan in primates, but how these influence each other

1104-407: Is not yet certain. Plants within a 12.5 kilometer foraging radius of the caves would have included 161 native species from a mix of geophytes / underground storage organs (USOs), leaves, and fruits, all of which would provide sufficient nutrients for the hominins at the site. By increasing the foraging radius to 35 kilometers away from the site, more nuts, seeds, and grains become available with

1173-489: Is passed through generations is argued as symbolic behavior by Sarah Wurz, the current primary investigator at the site. KRM's bone tools represent this symbolic behavior as they exhibit similar modifications and use-wear patterns that suggest they were used and created in the same way. Use of ochre is sometimes interpreted as symbolic behavior, however it also has practical purposes for paint or as an element of an adhesive. At KRM higher concentrations of red ochre are found in

1242-489: Is provided by analysis of ice cores . The SPECMAP Project, funded by the US National Science Foundation , has produced one standard chronology for oxygen isotope records, although there are others. This high resolution chronology was derived from several isotopic records, the composite curve was then smoothed, filtered and tuned to the known cycles of the astronomical variables. The use of

1311-421: Is the highest point in the range at 1675 m. The climate of the range is extremely mild, with temperature variations only between 10 °C and 25 °C generally and rainfall exceeding 1000 mm per annum, thus the region supports verdant fynbos and Afromontane temperate gallery forest habitats. Snow sometimes occurs on the highest peaks in winter. The topography of the mountains is interesting, in that

1380-678: The Khoekhoe language . The Tsitsikamma Range stretches just over 80 km from the Keurbooms River in the west just north of Plettenberg Bay , to Kareedouw Pass and the Eerste River in the east near the town of Kareedouw , and forms a continuous range with the Outeniqua Mountains to the west. The range consists almost exclusively of Table Mountain sandstone which is extremely erosion-resistant. Peak Formosa

1449-500: The Semliki River Valley , dating to around 90 ka, and at Blombos Cave dating to 73 ka. Researchers have also confirmed evidence of shell beads at Klasies River caves, which is corroborated by similar discoveries from other cave sites on the southern coast. The hominins at KRM were hunter-gatherers, and the presence of faunal remains, shellfish, and plant residues shows the wide variety of food sources available near

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1518-533: The Howiesons Poort lithics were made from a wider variety of materials and were fashioned into smaller blades and artifacts. Tools from MSA III are made from more non-local raw materials than MSA I or II, but less than Howiesons Poort; these tools from MSA III also have a similar core morphology to Howiesons Poort. The MSA IV lithics consist of more flake blades than observed in MSA III. Earlier layers from

1587-499: The Klasies River Caves site correlates with a MIS stage. The stratigraphy of the site consists of very fine, thin layers of sediment that have compressed under the successive layers on top of them. Researchers have used microstratigraphic techniques to analyze and interpret the complex timeline of sediment deposition and post-depositional activities within the caves. Because the cave system has so many varied layers and

1656-486: The Klasies site appear to have modern human morphology based on cranial traits. The specimens do not have retromolar spaces in the mandible and the supraorbital regions appear similar to other Homo sapiens specimens. The differences in some of the skull fragments are attributed to sexual dimorphism —differences in the size or robustness of the bone between sexes. Other anatomically modern Homo sapiens specimens from

1725-458: The MIS data. The sediments also acquire depositional remanent magnetization which allows them to be correlated with earth's geomagnetic reversals . For older core samples, individual annual depositions cannot usually be distinguished, and dating is taken from the geomagnetic information in the cores. Other information, especially as to the ratios of gases such as carbon dioxide in the atmosphere,

1794-610: The MIS timescale and the causal effect of the orbital theory. In 2010 the Subcommission on Quaternary Stratigraphy of the International Commission on Stratigraphy dropped other lists of MIS dates and started using the Lisiecki & Raymo (2005) LR04 Benthic Stack, as updated. This was compiled by Lorraine Lisiecki and Maureen Raymo . The following are the start dates (apart from MIS 5 sub-stages) of

1863-419: The MSA I and Howiesons Poort levels which may be evidence of ritual or symbolic use. Despite the evidence above, modern human behavioral models are still a contested issue. Arguments for origins of behavioral modernity rely on findings of hominin remains at prehistoric sites; this allows material culture and inferred behaviors to be correlated with the discovered remains. However, taphonomic processes produce

1932-467: The MSA I than in MSA II as indicated by use-wear analysis on stone tools and interpretation of shell middens. During the first excavation in 1967 by Singer and Wymer, a coarse sieve was used for screening causing the loss of smaller bones, shells, and other artifacts; because of this sample sized are biased because long bones (i.e. bone shafts) and small bones (i.e. finger bones) were not collected. However,

2001-595: The MSA II dates from 80-28 kya based on Uranium-Thorium and OSL dating within the same layer. This correlates with the Rockfall (RF) Member described by Deacon. Paleoenvironment reconstruction uses multiple analytical foci to help determine a proximate estimate of the climate of a site during a given time frame. These reconstructions are aided through archaeological excavations and finds. Analysis of faunal remains can indicate what species existed across space and time. Likewise, archaeobotanical analysis provides insight into

2070-616: The MSA IV. It does not contain many archaeological features such as hearths or material culture other than lithics. Current ethnobotanical research exploring the biodiversity of Klasies River and the Cape region found that many hunter-gatherer-pastoralists from the Khoi and San populations use the flora and fauna of the region that was also found in archaeobotanical and faunal assemblages. The study took an inventory of plants within 5 km of

2139-786: The MSA are found at sites in East Africa and in the Levant (see Omo Kibish , Mumba Cave , and Shkul Cave ). Researchers have turned to Africa as the birthplace of human behavioral modernity since it is also the place where modern humans evolved. Some researchers have proposed models and trait lists for behavioral modernity that has sparked intense debate among scholars about what constitutes modern human behavior. Evidence of woven grass beds at Border Cave , engraved ochre and beads at Blombos Cave , bone tool culture at Sibudu Cave , and incised ostrich eggshells from Diepkloof rock shelter have all been interpreted as complex behaviors. The debate about

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2208-745: The WS member (MIS IV). Only one deciduous tooth is attributable to Howiesons Poort levels (Upper Member). The Upper member (MSA III) contains two parietal fragments, 1 deciduous tooth, and one permanent premolar. The majority of remains came from the SAS member (MSA II) and post-HP included two vertebral fragments, five mandibular fragments, seven teeth without associated alveolar bone, one facial bone, one pelvis fragment, one clavicle, 15 cranial fragments, one radius and one ulna fragment, one manual distal phalanx, and three metatarsals. The LBS Member (MSA I) contained 27 cranial fragments and two mandibular fragments. A majority of

2277-524: The archaeological record; however exchange networks, alliances, and egalitarianism are also indicators of complex behavior. General: Tsitsikamma Mountains The Tsitsikamma mountains form an east-west mountain range located in the Garden Route region of the southern South African coast in the Western Cape and Eastern Cape provinces. Tsitsikamma means 'place of much water' in

2346-402: The authors suggest are more comparable to Holocene Khoesan populations. However, comparisons of prehistoric populations to modern populations are debated and may not have merit. Assessment of relatedness between species is based on ancestral or derived traits to create a phylogeny that assigns closely related specimens to the same or similar groups; this is usually visualized as branches on

2415-425: The bone point was also hafted within a reed, consistent with ethno-historic accounts of early hunter-gatherers from the region. Alternative interprations that include use as a domestic tool for woodworking or as a javelin point are not consistent with microwear of the bone point leading the authors to conclude that the bone tool was used as an arrowhead. Other bone points have been found at MSA sites including Katanda in

2484-473: The bones that were analyzed show anatomical differentiation within Homo sapiens throughout time. Over 50 human remains have been found, a majority of them from Singer and Wymer's original excavation in 1967-68, and a majority of these excavated in Cave 1. The human remains come from early Homo sapiens and the fragments show sexually dimorphic traits . The human remains from KRM are mostly fragmentary adult skeletal elements. No human remains were recovered from

2553-429: The caves. Critiques of the original excavation include sampling bias due to excavation and screening methods, and combination of stratigraphic layers that obscures the sites' complexity; certain strata were lumped together making it difficult to differentiate between activities at the site and combining artifacts and bones from multiple different strata. These initial findings prompted successive excavations to examine

2622-692: The coast of the Indian Ocean. The district receives approximately 500–700 mm (20–28 in) of rainfall annually. The site consists of Caves 1 and 2, and the protected overhangs of Cave 1A and 1B, together known as Klasies River main site. However, Cave 2 was not accessible until later stages after there had been significant deposition and build-up of sediments, and Cave 1B has been under-documented; most finds therefore come from Caves 1 and1A. These caves contain 21 meters of deposits that researchers have struggled to delineate stratigraphically. While sea levels fluctuated over time, during certain occupations,

2691-530: The coastline was likely never more than 10 km away from the site. The number of grazers decreased while mixed-feeders and browsers increased; this correlates with a decrease in shrubland and expanding grasslands. Terrestrial fauna include rock hyrax (rock rabbits), brown hyena , Cape dune mole rat , buffalo, equids , and members of the subfamily Alcelaphinae . There is also evidence of forest-dwelling bovid and other animals that prefer wetland grasses and reeds ( African marsh rat and hippopotamus), indicating

2760-413: The cranial bones, hand and foot bones. However, it is likely an error in excavation and collection from Singer and Wymer that has biased against the collection of human remains. An argument for cannibalism has been posed by some researchers. The fragmented human cranial fragments exhibit cut marks and charring similar to that of the faunal remains from the site. This treatment has led to the conclusion that

2829-406: The different caves have different depositional characteristics and sediment properties, it has been hard to create a uniform system to group and chronologically group the layers for a site-wide comparison; natural processes such as erosion, and the influence of people at certain areas of the site (anthropogenic deposition of shell middens , hearths, etc.) have further complicated the interpretation of

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2898-579: The entire series of stages then revealed unsuspected advances and retreats of ice and also filled in the details of the stadials and interstadials . More recent ice core samples of today's glacial ice substantiated the cycles through studies of ancient pollen deposition. Currently a number of methods are making additional detail possible. Matching the stages to named periods proceeds as new dates are discovered and new regions are explored geologically. The marine isotopic records appear more complete and detailed than any terrestrial equivalents, and have enabled

2967-458: The environmental diversity of the site during MSA II. Warm-water shellfish ( brown mussels and other rocky shore species) and cape fur seals were present at the cave as groups were able to exploit marine food sources as well. The Howiesons Poort (HP) environment shifts from the closed environment of the later MSA II into a more open environment featuring more grazing animals. The earlier levels of HP contain more evidence of browsers which indicate

3036-446: The fluctuations over time in the marine isotope ratios that had become evident by then were caused not so much by changes in water temperature, as Emiliani thought, but mainly by changes in the volume of ice-sheets, which when they expanded took up the lighter oxygen-16 isotope in preference to the heavier oxygen-18. The cycles in the isotope ratio were found to correspond to terrestrial evidence of glacials and interglacials. A graph of

3105-759: The individuals at Klasies remain the oldest case of hypercementosis in Sub-Saharan Africa (ca. 119 ka). This find is significant because it demonstrates continuity of the condition through the hominin lineage. Finger bones (manual distal phalanges) dating to 90-100 ka were also recovered from the Witness Baulk in Cave 1. These bones are from an adult individual and appear smaller in size than modern human populations; they are also not comparable to Neanderthal phalanges. These phalanges are however similar to phalanges originating in Die Kelders cave which

3174-528: The inhabitants participated in episodic cannibalism . Two individuals appear to be deposited around the same time in one stratigraphic layer, but correlating a site-wide cannibalism event requires a finer-scale understanding of the lithostratigraphy that is not possible at present. Of the remains recovered, two mandibles display the idiopathic dental anomaly of hypercementosis ; this condition has been discovered in Neanderthal and Homo erectus remains, but

3243-658: The microstratigraphy and refining the process of micro-scale excavations. This data allows comparison of KRM to other sites across the continent. The dates of the KRM stratigraphy have been obtained through isotopic analysis and dating of biological materials. Because the site exceeds 50,000 years old, radiocarbon dates are less useful due to carbon contamination. Researchers have resorted to analysis of unstable isotopes, such as Uranium-Thorium (U-Th) to provide more accurate date ranges. Marine isotope stages (MIS) are used to compare large-scale global temporal comparisons; each stage in

3312-405: The microstratigraphy of the site. Deacon excavated units one by one, independently of other units in the cave, recording the stratigraphy observed in each individual unit before grouping units together based on their shared stratigraphic patterns. Rather than use culture stratigraphy, Deacon used a hybrid strategy combining Singer and Wymer's culture stratigraphy and lithostratigraphy . He developed

3381-474: The modern Klasies site and discovered 268 species. Over 50% of these plants were medicinal and 43% were edible or had other uses as demonstrated from interviews with Khoi and San communities. While not all of these plant species may have existed during the Middle Stone Age, these findings still demonstrate the longevity of plant knowledge throughout the communities in the area. The study also noted that

3450-473: The most recent MIS (Lisiecki & Raymo 2005, LR04 Benthic Stack ). The figures, in thousands of years ago, are from Lisiecki's website. Numbers for substages in MIS 5 denote peaks of substages rather than boundaries. The list continues to MIS 104, beginning 2.614 million years ago. The following are the start dates of the most recent MIS, in kya (thousands of years ago). The first figures are derived by Aitken & Stokes from Bassinot et al. (1994), with

3519-471: The origin of modern human behavior originally began as an assumption that modern anatomy and modern behavior came as a package during the Upper Paleolithic , but the previously discussed evidence situates the debate in the Middle Stone Age as an early adaptation that accrued slowly over time. At Klasies River, the lithic techno-complexes are indicative of symbolic behavior as they change through

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3588-589: The peak point of MIS 5e, and 5.51, 5.52 etc. representing the peaks and troughs of the record at a still more detailed level. For more recent periods, increasingly precise resolution of timing continues to be developed. In 1957 Emiliani moved to the University of Miami to have access to core-drilling ships and equipment, and began to drill in the Caribbean and collect core data. A further important advance came in 1967, when Nicholas Shackleton suggested that

3657-430: The plants that were in proximity to the site. These determinations are also aided by global climate estimates provided by deep sea cores. Plant and animal remains can also be indicative of certain climates as species have certain climatic ranges and preferred biomes. Changes in the location of the sea shore and in the grassy or wetland areas surrounding the cave have been determined using these methods. MSA I fauna indicate

3726-545: The proximity to the coast and the surrounding grasslands provided marine life and terrestrial animals that were exploited by the caves inhabitants. From 1967-1968 John Wymer and Ronald Singer conducted excavations that revealed evidence of Middle Stone Age (MSA)-associated human habitation beginning approximately 125,000 years ago. Singer and Wymer excavated Caves 1, 1A and 1B, and part of Cave 2; using culture stratigraphy, they determined stages as MSA I, MSA II, Howiesons Poort, MSA III and MSA IV, which allowed comparison across

3795-524: The range and the ocean also bears the name Tsitsikamma and is characterised by some cattle farms, sparse settlements and dense Afromontane (Temperate) gallery forest. This region sits on a 200m high plateau between the mountains and steep cliffs which drop into the Indian Ocean . Bloukrans Bridge is on the border between the Eastern and Western Cape provinces, and sports the highest bungee jump in

3864-489: The range rises abruptly from the south at a very defined line that runs almost due east-west at the 34° south latitude. This is due to the very regular nature of the rise of the Table Mountain Sandstone in an anticline fold structure above the grade of the surrounding Tsitsikamma coastal plateau. The Tsitsikamma National Park lies just to the south of the range on the Indian Ocean . The region between

3933-548: The remains are cranial fragments, and these outnumber the post-cranial elements. This pattern has been argued to represent a pattern that is also observed in the faunal remains record. One argument proposes that the preferred elements are taken to the site and are preserved due to fragmentation from marrow collection e.g. the cranial bones are the preferred bones. Another argument suggests a collection bias in which post-cranial long bones were preferred and were not preserved because they were destroyed during marrow collection leaving only

4002-459: The research also directed at the climate some 120,000 years ago, during the last interglacial. The theoretical advances and greatly improved data available by the 1970s enabled a "grand synthesis" to be made, best known from the 1976 paper Variations in the earth’s orbit: pacemaker of the ice ages (in Science ), by J.D. Hays, Shackleton and John Imbrie , which is still widely accepted, and covers

4071-479: The sequence from MSA I through MSA III. Each sequence displays a different social convention for construction of stone tools (a techno-complex) that isn't based on raw material availability. However, Howiesons Poort is the only recognized techno-complex at Klasies River Caves because it is recognized as a techno-complex across Southern Africa; further studies may recognize techno-complexes from other culture-stratigraphies as well. Conventionalized artifact manufacture that

4140-443: The site dating to MIS 5d-e have a density of shellfish and debitage from stone tool production. This dense accumulation of animal remains, shell middens, and the remains from stone tool production indicate that the caves were used as a home base rather than an intermittent shelter during this period. At later times in the younger strata of the site, a higher density of stone tools and lower density of shellfish at later dates suggest that

4209-819: The site on this basis with the lowest level being Basal Gravels, followed by the Light Brown Sand (LBS) Member, the Rubble Brown Sand (RBS) member, the Shell and Sand (SAS) member, the Rockfall (RF) and Upper member, and the White Sand (WS) member. Some of these layers are then further subdivided. This system allows researchers to compare deposition patterns and contexts across the site in each cave which may have different dates because of differing deposition processes in each cave environment; some caves may not contain each member listed. MIS 3 *in Cave 1A,

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4278-543: The site was only used as a tool production site rather than a residential location. This change in mobility at KRM corresponds to a similar change during the same time period at Pinnacle Point . Bone tools have been found at KRM during the original excavations by Singer and Wymer coming from MSA II and Howiesons Poort strata. Three denticulated bone tools originating from an MSA II context resemble musical rasps found at other Middle Stone Age sites in Southern Africa. The bone rasps were fashioned out of bovid rib and long bone, but

4347-464: The site. Food consumption at the site consisted of marine and terrestrial animals, evidenced by shell middens and faunal remains of bovids. Scientists suggest that the wide availability and variation in food sources were the cause for the anatomically modern humans due to the nutrients required for larger brains and cognitive function. However other research on the relationship between brain size, longevity and social learning suggests that large brain size

4416-400: The stratigraphy. A lithostratigraphic and culture stratigraphic approach are both used at KRM today. Singer and Wymer's stages at KRM began at the base, MSA I, followed by MSA II, Howiesons Poort, MSA III, and MSA IV. These groupings are based on changes on stratigraphy and/or changes in material culture though time. Deacon chose to organize the site based on soil descriptions; he categorizes

4485-475: The tilt of the Earth's axis of rotation – the "orbital theory". Indeed, that the MIS data matched Milankovich's theory, which he formed during World War I, so well was a key factor in the theory gaining general acceptance, despite some remaining problems at certain points, notably the so-called 100,000-year problem . For relatively recent periods data from radiocarbon dating and dendrochronology also support

4554-422: The use of certain plant types for survival during climate changes , and proposed that humans in the past could have subsisted in similar ways. There is evidence for stone tool production at the site. Rounded quartzite cobbles appear to be the preferred material for stone tool production based on the recovery of raw materials at the site. Analysis of flakes and debitage indicate that free hand stone percussion

4623-585: The varied and complex stratigraphy . Hilary Deacon began work in Caves 1, 1A and 1B from 1984-1995 focusing on the arbitrary delineation (the "Witness Baulk") that Singer and Wymer used to differentiate Cave 1A from Cave 1, as these caves are actually continuous. While the Singer and Wymer excavation used units that were excavated uniformly across the cave layer by layer, successive excavations focused on different stratigraphic approaches. Deacon's excavations maintained

4692-613: The world. Marine isotope stages The MIS timescale was developed from the pioneering work of Cesare Emiliani in the 1950s, and is now widely used in archaeology and other fields to express dating in the Quaternary period (the last 2.6 million years), as well as providing the fullest and best data for that period for paleoclimatology or the study of the early climate of the Earth, representing "the standard to which we correlate other Quaternary climate records". Emiliani's work in turn depended on Harold Urey 's prediction in

4761-451: Was the primary method of tool production at Cave 1, and the prevalence of consistent and nearly uniform points suggest that these tools were the desired end product. Lithic artifacts do show variation through the various occupation stages of KRM. Howiesons Poort interrupts the relative uniformity seen in MSA I and MSA II: in the latter, large and long quartzite points and blades were the goal end products and were usually not retouched , while

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